American Oil and Gas Reporter - March 2019 - 59

SpecialReport: Unconventional Resource Science
JPGs, which is central to PHMSA's
changes.
To add another layer of complexity,
RF-safe distances are detailed by the Institute of Makers of Explosives in SLP
20-Safety Guide for the Prevention of
Radio Frequency Radiation Hazards in
the Use of Commercial Electric Detonators
(Blasting Caps).
SLP 20 contains a representative list of
transmitter types (ranging from standard
AM transmitters to television, CB radio
and cell phones) with associated safe distances from more than 3,000 feet for AM
transmitters down to five feet for cellular
signals (Table 2). The majority of serviceintensive well site operations take place
within 100 feet of the wellhead, making it
desirable to arm, test and service perforating
guns within this radius (Figure 2).
Because of the detonator's intrinsically safe design, the minimum safe
distance requirement is virtually eliminated. The design also enables parallel
well operations without depth restrictions
or radio silence. Normal well site operations can continue while the gun string
is lowered into and raised from the well.
Surface explosive handling is minimized,
and arming can be conducted at any
time without interrupting other well site
activities. This reduces surface downtime
and greatly limits risks to the environment or to personnel handling the system.
Field Operation
In field operations, this new, intrinsically safe detonator technology has delivered a dramatic impact on the reliability
and safety performance of perforating
operations. Before the system was introduced, companies using resistorized det-

TABLE 2
Safe Distances for 50 Ohm
Resistorized Detonators
Standard AM Transmitter

3,391 ft

17 ft

FM Transmitter

2,120 ft

24 ft

1,511-4,800 ft

73-77 ft

878 ft

4 ft

5 ft

0 ft

TV Transmitter, depending on
channel
Amateur/CB Radio
Cell Phone

onators experienced system efficiencies
of 98.0 percent, meaning that wireline
misruns or misfires occurred at a failure
rate of 2.0 percent.
After launch, the new system quickly
demonstrated efficiency that reached 99.41
percent, or one failure per 420 runs. With
continued refinement to system components, manufacturing and assembly
processes, along with well site operating
procedures, the efficiency rate now exceeds
99.9 percent and continues to increase.
In addition, each perforation stage run
with the system reduces completion time
by an average of 32 minutes, compared
with conventional systems. Surface-level
transitions from gun to gun and well to
well drive this time savings, resulting in
fewer days on location and significant
cost savings to operators.
Achieving greater efficiency in perforating systems can help lower overall
completion costs, particularly in long,
horizontal wellbores in unconventional
plays. The new, intrinsically safe detonator
arming process, with its fully factory-assembled perforating system design, a simplified mechanical field assembly process
and fewer failure points, is helping to reduce the number of misruns while increasing efficiency and minimizing costs.
Classified as a Group 2 "safe" deto-

DJR Energy Completes San Juan Basin Purchase
DENVER-DJR Energy LLC has completed its acquisition of Encana Corp.'s
San Juan Basin assets. DJR Energy says
it now holds the largest position in the
core of the New Mexico basin's oil window, with more than 350,000 net acres
and an inventory of more than 1,100
high-value drilling locations boasting
break-even prices competitive with other
premier oil basins.
With the acquisition, DJR says, it will
have production of 7,000 barrels a day of
oil equivalent and a gas midstream gathering system servicing its assets.
"We look forward to continuing to

Safe Distances for
Intrinsically Safe Detonators

unlock the potential of the southern San
Juan Basin, and believe DJR is well positioned as the dominant player in the oil
window," says Dave Lehman, the company's
president and chief executive officer. "Our
team has done an excellent job of preparing
for the transition, and we look forward to
commencing drilling operations."
Encana says the transaction by its subsidiary, Encana Oil & Gas (USA) Inc.,
completes its move to unlock value from
noncore assets, and supports the company's
commitment to its $1.25 billion share
buyback and 25 percent increase in dividends in 2019.
❒

nator, the system's ability to conduct
PHMSA-, SPL 20- and API RP 67-compliant operations, shipping and surface
testing greatly reduces the risk of an unintended detonation at any stage of explosive handling or transport. The intrinsically safe detonator design minimizes
the required safe zone at the well site
during the arming process and in the
post-run rig down.
Because the detonator and gun are
shipped to the well site as separate units,
the system complies with guidelines for
transportation that are documented in the
newly revised HMR; 49 CFR. With this
system, technology advancements have
delivered a perforating gun system that is
easier to arm and test, safer to transport
and handle, and more efficient to operate.
❒

THILO
SCHARF

Thilo Scharf is product line director
of DynaEnergetics' new DynaStageTM
factory-assembled, Performance-AssuredTM perforating system for improved
well site safety and efficiency. He joined
DynaEnergetics in 2011 after an 11year career at Schlumberger Oilfield
Services. His main areas of interest are
perforating technology, explosive safety
and oil well completion methods/techniques. Scharf holds an engineering degree in applied physics and biomedical
engineering from WHZ, Zwickau in
Germany, and an M.S. in nondestructive testing from the Robert Gordon
University in Scotland.
MARCH 2019 59

American Oil and Gas Reporter - March 2019

Table of Contents for the Digital Edition of American Oil and Gas Reporter - March 2019